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O48782 (HMOX1_ARATH) Reviewed, UniProtKB/Swiss-Prot

Last modified April 16, 2014. Version 94. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (2) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Alt products·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Heme oxygenase 1, chloroplastic

Short name=AtHO1
EC=1.14.99.3
Alternative name(s):
Protein GENOMES UNCOUPLED 2
Protein REVERSAL OF THE DET PHENOTYPE 4
Gene names
Name:HO1
Synonyms:GUN2, HY1, HY6, TED4
Ordered Locus Names:At2g26670
ORF Names:F18A8.4
OrganismArabidopsis thaliana (Mouse-ear cress) [Reference proteome]
Taxonomic identifier3702 [NCBI]
Taxonomic lineageEukaryotaViridiplantaeStreptophytaEmbryophytaTracheophytaSpermatophytaMagnoliophytaeudicotyledonsGunneridaePentapetalaerosidsmalvidsBrassicalesBrassicaceaeCamelineaeArabidopsis

Protein attributes

Sequence length282 AA.
Sequence statusComplete.
Sequence processingThe displayed sequence is further processed into a mature form.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Key enzyme in the synthesis of the chromophore of the phytochrome family of plant photoreceptors. Catalyzes the opening of the heme ring to form the open-chain tetrapyrrole biliverdin IX with the release of iron and carbon monoxide (CO). Produces specifically the biliverdin IX-alpha isomer. Can form complex with heme, is ferredoxin-dependent and its activity is increased in the presence of ascorbate. Plays a role in salt acclimation signaling. May affect the plastid-to-nucleus signaling pathway by perturbing tetrapyrrole synthesis. The plastid-to-nucleus signal plays an important role in the coordinated expression of both nuclear- and chloroplast-localized genes that encode photosynthesis-related proteins. Ref.1 Ref.2 Ref.8 Ref.9 Ref.10 Ref.11 Ref.12 Ref.13 Ref.14 Ref.16 Ref.17 Ref.18

Catalytic activity

Protoheme + 3 AH2 + 3 O2 = biliverdin + Fe2+ + CO + 3 A + 3 H2O. Ref.1 Ref.13

Enzyme regulation

Activated by ascorbate. Ref.13

Subcellular location

Plastidchloroplast Ref.1 Ref.16.

Tissue specificity

Widely expressed. Ref.2 Ref.14 Ref.17

Induction

By salt treatment. Down-regulated by jasmonate. Ref.13 Ref.15 Ref.17

Disruption phenotype

Long hypocotyl, incomplete chloroplast and leaf development, lack of photoreversible phytochromes and lack of phytochromobilin, the phytochrome chromophore. No cotyledon expansion in response to bright-red light. Increased levels of jasmonate (JA) and constitutive expression of JA-inducible defense genes. Increased sensitivity to salt stress and no acclimation response to salinity. Ref.1 Ref.2 Ref.7 Ref.8 Ref.9 Ref.10 Ref.11 Ref.14 Ref.15 Ref.17 Ref.18

Sequence similarities

Belongs to the heme oxygenase family.

Biophysicochemical properties

Kinetic parameters:

KM=1.3 µM for hemin Ref.13 Ref.16

KM=1.9 µM for ferredoxin

KM=420 µM for ascorbate

pH dependence:

Optimum pH is 7.2.

Sequence caution

The sequence AAK52998.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally extended.

Alternative products

This entry describes 2 isoforms produced by alternative splicing. [Align] [Select]
Isoform 1 (identifier: O48782-1)

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.
Isoform 2 (identifier: O48782-2)

The sequence of this isoform differs from the canonical sequence as follows:
     94-142: GEKETKSIEERPVAKWEPTVEGYLRFLVDSKLVYDTLELIIQDSNFPTY → D
Note: Derived from EST data. No experimental confirmation available.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Transit peptide1 – 5454Chloroplast Potential
Chain55 – 282228Heme oxygenase 1, chloroplastic
PRO_0000412185

Sites

Metal binding861Iron (heme axial ligand) By similarity

Natural variations

Alternative sequence94 – 14249GEKET…NFPTY → D in isoform 2.
VSP_041652

Sequences

Sequence LengthMass (Da)Tools
Isoform 1 [UniParc].

Last modified November 1, 1999. Version 2.
Checksum: 65D9638890A3E8BA

FASTA28232,691
        10         20         30         40         50         60 
MAYLAPISSS LSIFKNPQLS RFQFSSSSPN PLFLRPRIQI LSMTMNKSPS LVVVAATTAA 

        70         80         90        100        110        120 
EKQKKRYPGE SKGFVEEMRF VAMRLHTKDQ AKEGEKETKS IEERPVAKWE PTVEGYLRFL 

       130        140        150        160        170        180 
VDSKLVYDTL ELIIQDSNFP TYAEFKNTGL ERAEKLSTDL EWFKEQGYEI PEPTAPGKTY 

       190        200        210        220        230        240 
SQYLKELAEK DPQAFICHFY NIYFAHSAGG RMIGRKVAER ILDNKELEFY KWDGELSQLL 

       250        260        270        280 
QNVREKLNKV AEEWTREEKN HCLEETEKSF KYSGEILRLI LS 

« Hide

Isoform 2 [UniParc].

Checksum: D5350323BB620A1E
Show »

FASTA23427,076

References

« Hide 'large scale' references
[1]"The Arabidopsis photomorphogenic mutant hy1 is deficient in phytochrome chromophore biosynthesis as a result of a mutation in a plastid heme oxygenase."
Muramoto T., Kohchi T., Yokota A., Hwang I., Goodman H.M.
Plant Cell 11:335-348(1999) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA] (ISOFORM 1), FUNCTION, CATALYTIC ACTIVITY, SUBCELLULAR LOCATION, DISRUPTION PHENOTYPE.
Strain: cv. Landsberg erecta.
[2]"The Arabidopsis thaliana HY1 locus, required for phytochrome-chromophore biosynthesis, encodes a protein related to heme oxygenases."
Davis S.J., Kurepa J., Vierstra R.D.
Proc. Natl. Acad. Sci. U.S.A. 96:6541-6546(1999) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], FUNCTION, TISSUE SPECIFICITY, DISRUPTION PHENOTYPE.
Strain: cv. Columbia and cv. Landsberg erecta.
[3]"Sequence and analysis of chromosome 2 of the plant Arabidopsis thaliana."
Lin X., Kaul S., Rounsley S.D., Shea T.P., Benito M.-I., Town C.D., Fujii C.Y., Mason T.M., Bowman C.L., Barnstead M.E., Feldblyum T.V., Buell C.R., Ketchum K.A., Lee J.J., Ronning C.M., Koo H.L., Moffat K.S., Cronin L.A. expand/collapse author list , Shen M., Pai G., Van Aken S., Umayam L., Tallon L.J., Gill J.E., Adams M.D., Carrera A.J., Creasy T.H., Goodman H.M., Somerville C.R., Copenhaver G.P., Preuss D., Nierman W.C., White O., Eisen J.A., Salzberg S.L., Fraser C.M., Venter J.C.
Nature 402:761-768(1999) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
Strain: cv. Columbia.
[4]The Arabidopsis Information Resource (TAIR)
Submitted (APR-2011) to the EMBL/GenBank/DDBJ databases
Cited for: GENOME REANNOTATION.
Strain: cv. Columbia.
[5]"Empirical analysis of transcriptional activity in the Arabidopsis genome."
Yamada K., Lim J., Dale J.M., Chen H., Shinn P., Palm C.J., Southwick A.M., Wu H.C., Kim C.J., Nguyen M., Pham P.K., Cheuk R.F., Karlin-Newmann G., Liu S.X., Lam B., Sakano H., Wu T., Yu G. expand/collapse author list , Miranda M., Quach H.L., Tripp M., Chang C.H., Lee J.M., Toriumi M.J., Chan M.M., Tang C.C., Onodera C.S., Deng J.M., Akiyama K., Ansari Y., Arakawa T., Banh J., Banno F., Bowser L., Brooks S.Y., Carninci P., Chao Q., Choy N., Enju A., Goldsmith A.D., Gurjal M., Hansen N.F., Hayashizaki Y., Johnson-Hopson C., Hsuan V.W., Iida K., Karnes M., Khan S., Koesema E., Ishida J., Jiang P.X., Jones T., Kawai J., Kamiya A., Meyers C., Nakajima M., Narusaka M., Seki M., Sakurai T., Satou M., Tamse R., Vaysberg M., Wallender E.K., Wong C., Yamamura Y., Yuan S., Shinozaki K., Davis R.W., Theologis A., Ecker J.R.
Science 302:842-846(2003) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
Strain: cv. Columbia.
[6]"Full-length cDNA from Arabidopsis thaliana."
Brover V.V., Troukhan M.E., Alexandrov N.A., Lu Y.-P., Flavell R.B., Feldmann K.A.
Submitted (MAR-2002) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
[7]"Different roles for phytochrome in etiolated and green plants deduced from characterization of Arabidopsis thaliana mutants."
Chory J., Peto C.A., Ashbaugh M., Saganich R., Pratt L., Ausubel F.
Plant Cell 1:867-880(1989) [PubMed] [Europe PMC] [Abstract]
Cited for: DISRUPTION PHENOTYPE.
[8]"Phytochrome-deficient hy1 and hy2 long hypocotyl mutants of Arabidopsis are defective in phytochrome chromophore biosynthesis."
Parks B.M., Quail P.H.
Plant Cell 3:1177-1186(1991) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, DISRUPTION PHENOTYPE.
[9]"Signal transduction mutants of Arabidopsis uncouple nuclear CAB and RBCS gene expression from chloroplast development."
Susek R.E., Ausubel F.M., Chory J.
Cell 74:787-799(1993) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, DISRUPTION PHENOTYPE.
[10]"Light-stimulated cotyledon expansion in Arabidopsis seedlings (the role of phytochrome b)."
Neff M.M., Van Volkenburgh E.
Plant Physiol. 104:1027-1032(1994) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, DISRUPTION PHENOTYPE.
[11]"Interactions between hy1 and gun mutants of Arabidopsis, and their implications for plastid/nuclear signalling."
Vinti G., Hills A., Campbell S., Bowyer J.R., Mochizuki N., Chory J., Lopez-Juez E.
Plant J. 24:883-894(2000) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, DISRUPTION PHENOTYPE.
[12]"Arabidopsis genomes uncoupled 5 (GUN5) mutant reveals the involvement of Mg-chelatase H subunit in plastid-to-nucleus signal transduction."
Mochizuki N., Brusslan J.A., Larkin R., Nagatani A., Chory J.
Proc. Natl. Acad. Sci. U.S.A. 98:2053-2058(2001) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION.
[13]"Expression and biochemical properties of a ferredoxin-dependent heme oxygenase required for phytochrome chromophore synthesis."
Muramoto T., Tsurui N., Terry M.J., Yokota A., Kohchi T.
Plant Physiol. 130:1958-1966(2002) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, CATALYTIC ACTIVITY, ENZYME REGULATION, BIOPHYSICOCHEMICAL PROPERTIES.
[14]"Multiple heme oxygenase family members contribute to the biosynthesis of the phytochrome chromophore in Arabidopsis."
Emborg T.J., Walker J.M., Noh B., Vierstra R.D.
Plant Physiol. 140:856-868(2006) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, TISSUE SPECIFICITY, DISRUPTION PHENOTYPE.
[15]"Phytochrome chromophore deficiency leads to overproduction of jasmonic acid and elevated expression of jasmonate-responsive genes in Arabidopsis."
Zhai Q., Li C.B., Zheng W., Wu X., Zhao J., Zhou G., Jiang H., Sun J., Lou Y., Li C.
Plant Cell Physiol. 48:1061-1071(2007) [PubMed] [Europe PMC] [Abstract]
Cited for: INDUCTION, DISRUPTION PHENOTYPE.
[16]"Characterization of the haem oxygenase protein family in Arabidopsis thaliana reveals a diversity of functions."
Gisk B., Yasui Y., Kohchi T., Frankenberg-Dinkel N.
Biochem. J. 425:425-434(2010) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, SUBCELLULAR LOCATION, BIOPHYSICOCHEMICAL PROPERTIES.
[17]"Enzymatic ring opening of an iron corrole by plant-type heme oxygenases: unexpected substrate and protein selectivities."
Gisk B., Bregier F., Krueger R.A., Broering M., Frankenberg-Dinkel N.
Biochemistry 49:10042-10044(2010) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, TISSUE SPECIFICITY, INDUCTION, DISRUPTION PHENOTYPE.
[18]"Evidence of Arabidopsis salt acclimation induced by up-regulation of HY1 and the regulatory role of RbohD-derived reactive oxygen species synthesis."
Xie Y.J., Xu S., Han B., Wu M.Z., Yuan X.X., Han Y., Gu Q., Xu D.K., Yang Q., Shen W.B.
Plant J. 66:280-292(2011) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, DISRUPTION PHENOTYPE.
+Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
AB021857 Genomic DNA. Translation: BAA77758.1.
AB021858 mRNA. Translation: BAA77759.1.
AF132475 Genomic DNA. Translation: AAD22107.1.
AF132476 Genomic DNA. Translation: AAD22108.1.
AC003105 Genomic DNA. Translation: AAB95301.2.
CP002685 Genomic DNA. Translation: AEC07872.1.
CP002685 Genomic DNA. Translation: AEC07873.1.
AF327418 mRNA. Translation: AAG42008.2.
AF375414 mRNA. Translation: AAK52998.1. Different initiation.
AY129477 mRNA. Translation: AAM91063.1.
BT002327 mRNA. Translation: AAN86160.1.
AY087288 mRNA. Translation: AAM64841.1.
PIRT52457.
RefSeqNP_001118392.1. NM_001124920.1.
NP_180235.1. NM_128224.2.
UniGeneAt.23645.

3D structure databases

ProteinModelPortalO48782.
SMRO48782. Positions 88-277.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

BioGrid2560. 1 interaction.
STRING3702.AT2G26670.1-P.

Proteomic databases

PRIDEO48782.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblPlantsAT2G26670.1; AT2G26670.1; AT2G26670. [O48782-1]
GeneID817208.
KEGGath:AT2G26670.

Organism-specific databases

TAIRAT2G26670.

Phylogenomic databases

eggNOGNOG308332.
HOGENOMHOG000265822.
InParanoidO48782.
KOK00510.
OMAGGRMIGR.
PhylomeDBO48782.
ProtClustDBCLSN2683416.

Enzyme and pathway databases

BioCycARA:AT2G26670-MONOMER.
MetaCyc:AT2G26670-MONOMER.

Gene expression databases

GenevestigatorO48782.

Family and domain databases

Gene3D1.20.910.10. 1 hit.
InterProIPR016053. Haem_Oase-like.
IPR016084. Haem_Oase-like_multi-hlx.
IPR016951. Haem_Oase_decyc_pln.
[Graphical view]
PfamPF01126. Heme_oxygenase. 1 hit.
[Graphical view]
PIRSFPIRSF030219. Heme_Oase_decyc_pln. 1 hit.
SUPFAMSSF48613. SSF48613. 1 hit.
ProtoNetSearch...

Entry information

Entry nameHMOX1_ARATH
AccessionPrimary (citable) accession number: O48782
Secondary accession number(s): B3H4A6, Q7E9A5, Q9FPE3
Entry history
Integrated into UniProtKB/Swiss-Prot: July 27, 2011
Last sequence update: November 1, 1999
Last modified: April 16, 2014
This is version 94 of the entry and version 2 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programPlant Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families

Arabidopsis thaliana

Arabidopsis thaliana: entries and gene names